Testing VUNA fertilisers on crops
In VUNA affiliated projects, our fertilisers are being tested in South Africa and Switzerland. At the UKZN Agricultural Engineering Department in Pietermaritzburg, crop scientists fertilised maize in a pot trial with struvite, dehydrated and pasteurised latrine faecal sludge pellets and commercial superphosphate. First results have shown that struvite gave the best results as phosphorus fertilisers on clayey soils, but efficiency strongly depended on soil characteristics.
At ETH in Zurich, the Plant Nutrition Group produced isotope-marked struvite and nitrification/distillation product. The tests in ETHZ's greenhouse have shown that plants assimilate nutrients from VUNA fertilisers at least as readily as from commercial synthetic fertilisers.
In 2015, the Swiss Federal Office of Agriculture (FOAG) issued a temporary license for the VUNA fertiliser to be used on flowers, lawn, and ornamental plants. To extend the license beyond 2018, Eawag needs to provide further results on how to completely eliminate pharmaceutical residues from the fertiliser product.